1. Field of the Invention
The present invention relates to the field of the agricultural machines and more particularly refers to a seeding machine with a cutting disc or coulter for cutting the stubble remaining on the soil and even more particularly the invention refers to a new system for mounting the coulter in a minimum tillage or no tillage machine in a manner to improve the cutting effect of the coulter on the stubble and harvest leftovers which remain in the field, ahead of the planting unit, by keeping a uniform and constant penetration of the coulter into the soil along the seeding path.
2. Description of the Prior Art
The increasing concern of the environment was, among other questions, one of the points that driven new technologies for agricultural seeding methods that were replacing the traditional row crop farming. Minimum tillage or non tillage farming equipments employs many implements capable of performing multiple functions simultaneously. No tillage farming equipments have been in use for decades and many improvements have been and are constantly implemented for better results.
A seeding machine generally comprises a frame upon which a plurality of ground working implements or tools are mounted to till and plant row crops in one pass of the field. The machine employs a plurality of planting units, one for each line of crops or furrows and the tools are arranged serially one behind the other in the direction of travel of the machine. For example, counter means are arranged at the front of the frame to split and slice the untilled ground directly in front of the planter unit travelling behind. Once the stubble and rests of old crops remaining on the field is cut and open, the planter unit forms a furrow, deposits the seeds and covers up the seeds. The planter units is provided with furrow opening discs conveniently associated to some kind of seed supplier such as a seed tube or conduit, compacting wheels for compacting the soil at the sides of the furrow and finally closing wheels to cover up the seeds with loose soil. Other implements may be included for applying fertilizers, for example.
The general array of planter units will vary depending on the machine manufacturer, services, kind of crops, soils, etc. but generally all of them needs of a leading coulter or cutting disc for split and slicing the stubble. This leading coulter is a cutting disc that is rotatably mounted in a support in front of the planter unit generally by means of a pivoting mechanism, such as a deformable parallelogram whereby the disc may move up and down for copying, as much as possible, the irregularities and profile of the field. For exerting a downward force on the disc to guarantee a correct split and slice of the material remaining over the field, one or more springs are provided pushing the mechanism downwardly into the laying material or stubble and a surface of the soil. A release latch or similar lock is also provided to release the force on the disc when a solid obstacle is found in the disc path.
There is a variety of improvements in the art for mounting the tools and coulters, by different pivoting mounts that actuates on the coulter to make it copy the filed profile. Some of the alternatives employ one or more springs and pneumatic chambers to urge the coulter against the field. In addition, the provision of pneumatic chambers needs of additional room and installations for connections and operation.
However, the fields that is being worked is generally irregular and the planter unit, the tools in general, and particularly the coulter, can not keep a uniform deep, in the split of the stubble and furrow because the coulter my be in a level of the field above the level where the planter unit is working. The result of this uneven position of the equipment is that the coulter may be travelling deep under the surface of the soil while the planter unit has the tools thereof, such as the furrow opening discs, at a swallow furrow insufficient to provide a good covering for the seed. Generally, if the leading coulter finds a higher field level tends to lift all the equipment, including the planter unit.
Another effect on the coulter is that the force that urges the same into the stubble and slightly into the soil is also comprised of the weigh of the seed box, therefore when the box is full of seeds a good weight is transferred to the coulter mount but this weight may be insufficient when the box has a small amount of seeds. Hence, the coulter actuates only under the force of the springs.
Considering the above drawbacks of the prior art equipment, it would be very desirable and convenient to have a system for mounting a coulter in a seeding machine that may be combined with mounting of the planter unit in a manner that the force urging the coulter into the soil is affected by the position of the planter unit.